Affective characteristics of depressed and well mothers are investigated in relation to the affect and behavior of their children. The moods and emotions observed in the parent and experienced in interaction with the parent are significant socialization influences on the child's own affective development. The affective impairments that are characteristic of depression, if manifested by depressed mothers in their interactions with their children, are likely to create unpredictable, noncontingent, and stressful daily experiences for their children. The questions of interest concern the nature of mother's affective profile, the concordances between mother and child's moods and emotions, the relation of affect to other aspects of child development. When mother and child are analyzed as pairs, there is a high degree of concordance in their affective expression regardless of mother's diagnosis or gender of child. Depressed mother-child dyads are most frequently concordant in negative affect. Mutual positive affect between mother and child is significantly diminished in families characterized by disorganization or chaotic life conditions. The mutual positive affect at 2 to 3 years is predictive of the child's ability three years later to relate competently to unfamiliar peer.